That film clip was shot while I was asleep as we were getting near Aden, Yemen.
I wasn't awake, and so I can't attest to the exact sea state that was happening in the clip. The sequence shows that we are having some wave slap against the bridge deck
at that particular moment.
If Exit Only is going to pound, it will happen when we are sailing to windward. On a close reach, beam reach, broad reach or run, pounding isn't a problem. Whether or not we will pound sailing to windward depends on the sea state.
I think it's helpful to differentiate between waves thumping the bridge deck from what I call real pounding.
Wave slap happens when seas trapped between the hulls give the bridgedeck a thump.
Pounding is much different. With pounding, the entire vessel is rising up and crashing down with the whole bridgedeck interacting with sea, and the boat shuddering on the impact.
Wave slap doesn't bother me or concern me. We sailed for eleven years around the world without any structural problems to our bridgedeck.
Pounding bothers me a great deal and I didn't do it very often on Exit Only. I wouldn't abuse my boat by driving it hard into seas where the bridgedeck would impact the sea in a major way.
When Robin Knox Johnson and Peter Blake won the Jules Verne Trophy sailing around the world in under eighty days in ENZA New Zealand
, they had a pod/cabin between the two hulls called the "Godpod". They sailed so hard and so fast that the "Godpod" fractured from the pounding that it took. They didn't have wave slap. They had serious pounding that did structural damage.
I lived in Puerto Rico
for five years, and when I sailed my 32 foot monohull to windward to Saint Thomas, I experienced pounding that made the whole hull
shudder under the strain. There is no way I could have slept while pounding my way to windward.
I have two friends that sailed their monohulls from Florida
to Puerto Rico
, and in pounding their way to windward, they both broke bulkheads loose. In the Marquesas
, I met a 37 foot heavily laid up monohull that broke all the bulkhead lose in the galley
, and the galley
was free floating inside the boat with the damage caused by pounding.
In my experience, pounding creates structural damage. Bridgedeck slap by waves trapped between the hulls does not create structural damage. Some people even sleep through it.
I don't think this is semantics. It's the real world of offshore
cruising. If you sail to windward, sometimes you will have bridgedeck slap, and sometimes you will have pounding.
I guess one man's bridgedeck slap is another man's pounding.